Lind / Marchal / Wathen

Statistical Techniques in Business and Economics

F o u rte e n th E d ition

This International

Student Edition is for use outside of

the U.S.

M c G R A W - H I L L I N T E R N A T I O N A L E D I T I O N

S t a t i s t i c a l T e c h n i q u e s in

Business & EconomicsF o u r t e e n t h E d i t i o n

Douglas A. LindCoastal Carolina University and The University of Toledo

William G. MarchalThe University of Toledo

Samuel A. WathenCoastal Carolina University

McGraw-Hill Irwin

Boston Burr R idge, IL D ubuque . IA M adison, Wl New York San F ranc isco St Louis B angkok Bogota C aracas Kuala Lum pur L isbon London M adrid M ex ico C ity M ilan M ontrea l N ew Delhi Santiago Seoul S ingapore S ydney Taipei Toronto

MeGravuHill

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M T ilti i. „ . . im a a a l

McGraw-Hill Irwin

ST A TIST IC A L T E C H N IQ U E S IN BU SIN E SS AND EC O N O M IC SP ub lish ed by M cG raw-H ill/Irw in, a business un it o f T h e M cG raw-H ill C om panies, Inc., 1221 Avenue of the A m ericas, New York, NY, 10020. C opyright © 2010, 2008, 2005, 2002, 1999. 1996, 1993, 1990, 1986, 1982, 1978, 1974, 1970, 1967 by The M cG raw -H ill C om panies, Inc. All rights reserved. No part o f this pub lication m ay be reproduced or d istributed in any form or by any m eans, or stored in a database or retrieval system, w ithout the prior w ritten consent of T h e M cG raw-H ill C om panies, Inc.. includ in g, but not lim ited to. in any network or other e lectro n ic storage or transmission, or broadcast for d istance learn ing.

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T h is book is p rin ted on acid-free paper.

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ISBN 978-0-07-017220-3 M H ID 0 -07-017220-X

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The McGraw-Hill/Irwin Series Operations and Decision Sciences

Business Statistics

Aczel and SounderpandianComplete Business S tatisticsSeventh EditionALEKS CorporationALEKS fo r Business S tatisticsFirst EditionAlwanStatistica l Process AnalysisFirst EditionBowerman, O'Connell, and Murphree Business S tatistics in Practice Fifth Edition Bowerman, O’Connell,Orris, and MurphreeEssentials o f Business S tatisticsThird EditionBryant and SmithPractical Data Analysis: CaseStudies in Business Statistics,Volumes I, II, and III*Cooper and Schindler Business Research M ethods Tenth EditionDoane, Mathieson, and TracyVisual S ta tis ticsSecond Edition, 2.0Doane and SewardApplied S ta tis tics in Businessand Econom icsSecond Edition

Doane and SewardEssential S tatistics in Businessand EconomicsSecond EditionGitlow, Oppenheim, Oppenheim, and LevineQuality ManagementThird EditionKutner, Nachtsheim, Neter and Li Applied Linear Statistical ModelsFifth EditionKutner, Nachtsheim, and NeterApplied Linear Regression ModelsFourth EditionLind, Marchal, and WathenBasic S tatistics fo r Business andEconomicsSixth EditionLind, Marchal, and WathenStatistical Techniques in Businessand EconomicsFourteenth EditionMerchant, Goffinet, and KoehlerBasic S tatistics Using Excel forOffice XPFourth EditionOlson and ShiIn troduction to BusinessData M iningFirst EditionOrrisBasic S tatistics Using Excel and MegaStatFirst Edition

SiegelPractical Business S tatisticsFifth EditionWilson, Keating, and John Galt Solutions, Inc.Business ForecastingFifth Edition ZagorskyBusiness Inform ationFirst Edition

Quantitative Methods and Management Science

Hillier and Hillier In troduction to Management Science Third Edition Stevenson and Ozgur In troduction to Management Science w ith Spreadsheets First Edition KrosSpreadsheet M odeling fo r Business DecisionsFirst Edition

•Available only through M cG raw-H ill’s PRIMIS Online Assets Library.

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A Note From

O ver the years, w e have received m any co m p lim e n ts on th is te x t and have been to ld i t ’s a favo rite am ong s tuden ts . We a cce p t th a t as th e h ighest c o m p lim e n t and co n tin u e to w o rk very hard to m a in ta in th a t sta tus.

The o b je c tive o f S ta tis tica l Techniques in B usiness a n d E co n om ics is to p rov ide s tu d e n ts m a jo ring in m anagem ent, m arke ting , finance , a ccou n tin g , econ o m ics , and o th e r fie ld s o f bus iness a d m in is tra tio n w ith an in tro d u c to ry su rve y o f th e m any a pp lica tio n s o f d esc rip tive and in feren tia l s ta tis tics . W h ile w e fo c u s on bus iness a pp lica tions , w e a lso use m any exerc ises and exam p les th a t are s tu d e n t o rien ted and d o n o t require p rev ious courses.

In th is te x t w e sh ow beg inn ing s tu d e n ts every s te p needed to be su ccess fu l in a bas ic s ta tis tics course . Th is s te p -b y -s te p a pp roach enhances p e rfo rm ance , a c c e l­e rates p reparedness, and s ign ifica n tly im proves m o tiva tio n . U nd e rs ta n d in g th e c o n ­cep ts , seeing and do ing p len ty o f exam p les and exerc ises, and c o m pre h e nd ing the app lication o f s ta tis tica l m e thods in business and e conom ics are the focus o f th is book.

The firs t ed itio n o f th is te x t w as pub lished in 1967. A t th a t tim e loca ting re le­va n t bus iness da ta w as d ifficu lt. Tha t has changed ! Today loca tin g da ta is n o t a p rob lem . The num ber o f item s you purchase at the g roce ry s to re is au to m a tica lly recorded a t the ch e cko u t counter. P hone com pa n ies tra c k th e tim e o f o u r ca lls , the leng th o f ca lls, and the num ber o f th e person ca lled . C red it ca rd co m p a n ie s m a in ­ta in in fo rm a tion on the num ber, tim e and date , and a m ou n t o f o u r pu rchases. M e d ­ical d ev ices au to m a tica lly m o n ito r o u r heart rate, b lo o d pressure , and tem pera tu re . A large am ou n t o f bus iness in fo rm a tion is reco rded and re po rted a lm o s t instantly. CNN , USA Today, and M S N B C , fo r exam p le , all have w eb s ite s w he re you can tra ck s to c k p rice s w ith a de lay o f less than 20 m inutes.

Today, sk ills are needed to deal w ith a large vo lu m e o f n um erica l in fo rm a tion . First, w e need to be c ritica l co nsu m e rs o f in fo rm a tion p resen ted b y o the rs . S econd , w e need to be able to reduce large a m ou n ts o f in fo rm a tio n in to a c o n c ise and m e an ­ing fu l fo rm to enab le us to m ake e ffe c tive in te rp re ta tions , jud g m e n ts , and d ec is ions .

A ll s tu d e n ts have c a lc u la to rs and m o s t have e ith e r pe rso n a l c o m p u te rs or a cc e s s to pe rso n a l c o m p u te rs in a ca m p u s lab. S ta tis tic a l so ftw a re , su ch as M ic roso ft Excel and MINITAB, is ava ilab le on these co m p u te rs . The c o m m a n d s n e c ­essary to ach ieve th e so ftw a re resu lts are ava ilab le in a spec ia l se c tion at th e end o f each chap ter. We use screen c a p tu re s w ith in th e c h a p te rs , so th e s tu d e n t becom es fa m ilia r w ith the nature o f th e so ftw a re o u tp u t. B ecause o f th e a va ilab ility o f co m p u te rs and so ftw a re it is no longe r necessa ry to dw e ll on ca lcu la tion s . We have rep laced m any o f the c a lcu la tion exam p les w ith in te rp re ta tive ones, to ass is t the s tu d e n t in und e rs ta n d in g and in te rp re ting th e s ta tis tica l resu lts . In a dd itio n w e n ow p lace m ore e m phas is on th e co nce p tu a l na tu re o f th e s ta tis tica l to p ic s . W h ile m ak ing these changes, w e still co n tin u e to p resen t, as b es t w e can, th e key c o n ­ce p ts , a long w ith s u p p o rtin g exam p les.

What's New in This Fourteenth Edition?We have m ade severa l chan g e s to th is e d itio n th a t w e th in k you a nd yo u r s tu d e n ts w ill fin d useful.

• N ew exercises and exam p les using Excel 2007 screensho ts and the la test version o f MINITAB. We have also increased the size and c la rity o f these screenshots.

IV

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ithors

There are a lso new Excel 2007 so ftw are com m ands and upda ted MINITAB c o m ­m ands at the ends o f chap ters.A t th e end o f each S ection Review, w e have added a P rac tice Test. We th ink th is w ill g ive the s tuden t an idea o f w ha t m igh t appea r on a te s t and how the te s t m igh t be s tru c tu re d . H opefu lly, th is w ill reduce te s t anxie ty. The te s t inc ludes a sec tion on vocabu lary and a sec tion o f p rob lem s.We have carefu lly review ed the Exercises w ith in the chap ters , those at the ends o f chap ters, and in the Review S ection. We have revised o r rep laced those th a t w ere ou tda ted . You can still find and assign your favo rites th a t have w orked well, o r you can in troduce fresh exam ples.There is new con ten t on nom ina l-leve l data and its p roperties in C hap te r 1. There are m any new pho tos th ro u gh o u t w ith upda ted exerc ises in the chap te r openers.M uch o f the re levant da ta and s ta tis tics w ith in the te x t and exerc ises have been updated.

D edication

To ¡ane, my wife and best friend, and our sons, their wives, and our grandchildren: Mike and Sue (Steve and Courtney), Steve and Kathryn (Kennedy and lake), and Mark and Sarah dared. Drew, and Nate).

Douglas A. Lind

To Elizabeth and William, the most recent additions to our family.

William G . Marched

To my wonderful family: Isaac, Hannah, and Barb.

Samuel A. WathenSô hoa bơi Trung tâm Hoc liêu – ĐH TN http://www.lrc-tnu.edu.vn

How Are Chapters Organized to

Chapter GoalsEach chap te r beg ins w ith a set o f goals, o r learning objectives, designed to p rov ide focus fo r the chap te r and m otivate s tu ­d en t learn ing. These ob je c tive s ind ica te w ha t the s tu d e n t shou ld be able to do a fte r com ple ting the chapter.

Chapter Opening ExerciseA representative exercise opens the chap te r and show s how the ch ap te r co n te n t can be app lied to a real w orld s ituation.

Introduction to the TopicEach chapter starts w ith a review of the im por­tant concepts o f the previous chapter and pro­vides a link to the material in the current chapter. This s tep -by-s tep approach increases com pre­hension by providing continuity across the con­cepts.

IntroductionThe highly competitive automotive retailing business has changed significantly over the past 5 years, due in part to consolidation by large, publicly owned deal­

ership groups. Traditionally, a local family owned and oper­ated the community dealership, which might have Included one or two manufacturers, like Pontiac and GMC Trucks o Chrysler and the popular Jeep line Recently, however, skill fully managed and well-financed companies have beei acquiring local dealerships across large regions of the coun try. As these groups acquire the local dealerships, they often bring standard selling practices, common software and hard­ware technology platforms, and management reporting tech­niques The goal is to provide an improved buying expi ence for the consumer, while increasing the profitability of

Example/SolutionA fte r im p o rta n t co n c e p ts are in troduced , a so lved exam ple is g iven to p rov ide a how -to illus tra tion fo r s tuden ts and to show a relevant business o r e conom ics-based app lication tha t helps answ er the question , “ W hat will I use th is fo r? " All exam ples provide a realistic scenario o r a pp lica tio n and m ake th e m ath s ize and sca le reasonable fo r in trod u c to ry s tudents.

Self-ReviewsSelf-Reviews are interspersed th rough­out each chapter and closely patterned after the preceding Examples. They help students m on ito r the ir progress and provide im m ediate reinforcem ent fo r that particular technique.

Self-Review 3-2 Spnngers sold 95 Antonelli men s suits for the regular price of $400. For the spring sale the surts were reduced to $200 and 126 were sold. At the final clearance, the pnce was reduced to $100 and the remaining 79 suits were sold, la) W*3’ "a s ,he weighted mean pnce of an Antonelli suit?

■ H g r S ? . (b) Springers paid S200 a suit for the 300 suits. Comment on the store's profit per suit if 'B&BESgggP a salesperson receives a S25 commission for each one sold

Describing DataNumtrKjl M u u rn

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Engage Students and Promote Learning?

Statistics in ActionS ta tis tics in A c tio n a rtic les are sca tte red th rough ­ou t the tex t, usually abo u t tw o per chapter. They p rov ide unique and in teresting app lica tions and h is to rica l ins igh ts in the fie ld o f s ta tis tics .

Margin NotesThere are m ore than 300 co nc ise notes in the m argin . Each is a im ed at reem phasiz ing the key c o n c e p ts p resen ted im m ed ia te ly a d ja ­ce n t to it.

DefinitionsD efin itions o f new te rm s or te rm s unique to the study o f s ta tis tics are set apart from the text and h igh lighted fo r easy reference and review.

Variance and Standard DeviationVariance and standard The variance and standard deviation are also based on the deviations from the deviation a/e Based on mean However, instead of using the absolute value of the deviations, the variance squared derations from and the standard deviation square the deviations

VARIANCE The arithmetic mean of the squared deviations from the mean

The vanance is nonnegative and is zero only if all observations are the same

FormulasForm u las th a t are used fo r th e firs t tim e are boxe d and num bered fo r re ference. In add ition , a fo rm u la ca rd is bou n d in to the back o f the te x t, w h ich lis ts these key fo rm u las.

ExercisesE xercises are inc luded a fte r sec tions w ith in the c h ap te r and at the end o f the chapter. Section exerc ises cover the m ateria l s tud ied in the sec­tion.

Exercises______________________________15. Molly's Candle Shop has several retail stores in the coastal areas of North and South

Carolina. Many of Molly's customers ask her to ship their purchases The following chart shows the number of packages shipped per day for the last 100 days.

a. What is this chart called?b. What ¡s the total numper of frequencies'*

POPULATION VARIANCE

Computer OutputThe te x t inc lu d es m any so ftw a re exam ples, using Excel, M egaStat®, and MINITAB. Screen ca p tu res are h igh ligh ted w ith e ithe r a MINITAB o r Excel logo in th e m argin.

1

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m : CD

How Does This lëxt

BY CHAPTER

Chapter SummaryEach c h a p te r co n ta in s a b rie f su m m ary o f the c h a p te r m a te ria l, in c lu d in g th e vo c a b u la ry and th e c r itic a l fo rm u las .

Chopter SummaryI. A frequency table is a grouping o

mg me numb» of OK ------II. A relative frequency la

into mutually exclusive classes si

rs the fraction of the number of frequencies in each cl

Pronunciation KeyTh is to o l lis ts th e m a th e m a tica l sym b o l, its m e an ­ing, and h o w to p ro n o u n ce it. W e be lieve th is w ill he lp th e s tu d e n t re ta in th e m ean ing o f th e sym b o l and gen e ra lly enh a n ce co u rse c o m m u n ica tio n s .

P ro n u n c io t io n K e yMEANING PRONUNCIATION

Population mean muOperation of adding sigmaAdding a group of values sigma XSample mean X bar

Chapter ExercisesGenerally, th e end o f ch ap te r exerc ises are the m ost challeng ing and integra te the chap te r c o n ­cepts . The answ ers and w o rke d -o u t so lu tions fo r all odd -n u m be re d exercises appear a t the end of the text. For exercises w ith m ore than 20 obse r­vations, the da ta can be found on the S tudent CD and on the te x t’s W eb site. These files are in Excel and M INITAB fo rm ats.

C h o p te r € x e rc is e s23. Descnbe the similarities and differences of qualitative and quantitative variables. Be sure

to include:a. What level of measurement is required for each vanable type?b. Can both types be used to descnbe both samples and populations?

Data Set ExercisesT h e las t se ve ra l e xe rc is e s a t th e e nd o f e ach c h a p te r are b a s e d on fo u r la rge d a ta se ts . T h e se d a ta s e ts a re p rin te d in A p p e n d ix A in th e te x t and are a lso on th e S tu d e n t CD and on th e te x t ’s W eb s ite . These d a ta se ts p re se n t th e s tu ­d e n ts w ith re a l-w o r ld a n d m o re c o m p le x a p p lic a tio n s .

Software CommandsS o ftw a re e xa m p le s u s ing E xce l, M egaStat® , and M IN ITAB are in c lu d e d th ro u g h o u t th e te x t. B ut, th e e x p la n a tio n s o f th e c o m p u te r in p u t c o m ­m a n d s fo r each p ro g ra m are p la ce d a t th e end o f th e chap te r. T h is a llo w s s tu d e n ts to fo c u s on th e s ta tis tic a l te c h n iq u e s ra th e r th a n h ow to in p u t da ta .

1. The E*cei commands to select a s.rrx*e random sampie on page 26' are:a. Select tne Data tab on the top ol tne menu

Thenon the far nght select Data Analysis, men

b. Fey Input Range insert BI B3’ &nce the col­umn a named, click the Labels bo*. Select Random, and enter the sample sa» for the Number of Samples. • this case 5 Ok« or. Output Range and indicate the place m the spreadsheet you want the sample »itormatjon Note that your sample results after from those n Ihe text Also recall that Excel samples wth replacement, so it « possible for a popo-

samp*e

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Reinforce Student Learning?Answers to Self-ReviewThe w o rke d -o u t so lu tions to the Self-Reviews are prov ided at the end o f each chapter.

BY SECTION

Section ReviewsA fte r se le c te d g ro u p s o f c h a p te rs (1 -4 , 5 -7 , 8 and 9, 1 0 -1 2 , 13 and 14, 15 and 16, and 17 and 18), a S e c­t io n R eview is inc lu d ed . M uch like a rev iew be fo re an exam , these inc lude a b rie f overview o f the chap ters, g lossary o f key te rm s, m u ltip le -c h o ic e qu es tio ns , and p ro b lem s fo r rev iew .

CasesThe rev iew a lso in c lu d e s co n tin u ing cases and severa l sm a ll c a se s th a t le t s tu d e n ts m ake d e c is io n s us ing to o ls a nd te c h n iq u e s fro m a va rie ty o f ch ap te rs .

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Glossary '

________________________ ~ I

Practice TestThe P ra c tic e Test is in te n d e d to g ive s tu d e n ts an idea o f c o n te n t th a t m ig h t a p p e a r on a te s t and how th e te s t m ig h t b e s tru c tu re d . The P ra c tice Test in c lu d e s b o th o b je c tiv e q u e s tio n s and p rob le m s c o v ­ering th e m a te ria l s tu d ie d in th e sec tion .

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